She clearly set him up, but she didn't force him to whip her with the belt, nor was that faked in any way. The problem in the video is his behaviour. You may think she was wrong to secretly video tape him, but that doesn't make what he's doing any less wrong.
I think it's reasonable to expect a parent of a disabled (oh yeah, did you all catch that in the articles? she has cerebral palsy) child not to beat the kid, no matter what the kid "incites."
Ironic that he's standing over her to get results, and now frowning on her standing over him (with the video) to get results. I guess when you teach them that a spanking is how you get compliance, you can't be surprised when they leverage over the car/money/whatever else.
Edit: I'm thinking, maybe after he loses his next election, he can get a job with the RIAA - they're probably delighted to see parents whipping their children over illegal downloads. He can be a spokesman for RIAA approved parenting!